Facts of Light #2 - when green isn't good

LED downlights trick #2

If you’ve ever attended one of my lighting workshops, you’ll know that I spend a lot of time talking about colour in light.  Understanding colour (K) has never been more important in the world of lighting.  So what is it and why does it matter?

 Light comes in a huge range of colour temperatures.  You may have heard terms like warm white, cool white, daylight – these are all great descriptors for light temperature. 

The problem starts when you buy something called cool white or warm white that isn’t – and once you’ve seen it, you’ll never be able to ignore it again.

When you look at LED – deciding where you should use them, and how good they are value for money wise – you have to think GREEN.  Or PINK.  Or BLUE as well as WARM or COOL.  LED is notorious for producing light with a green tint, which tends to make everyone look ill, pink which can be OK, so long as it’s not combined in the same room with a blue white or green white, and of course the cold blue that everyone has seen in low quality LED.

 So, when looking at LED, check that is says warm white, or cool white, or 3000K, 3500K, 4000K – anything in that region.  If it lists 5000K or higher, chances are it’s going to look very blue, and most likely is not what you want in your home. Now here comes the important bit


All good lighting professionals do this. It’s vital to check that it is WHITE (not GREEN, PINK etc.) and that it is the warm or cool you want.  Turning them on is a great time to check for glare too.  If you’re not sure what you’re looking for, check out a cool and warm CFL lamp – they show it clearly and reliably.